Grand Seiko Ref. SBGH037, fitted with the brand’s hi-beat mechanical movement.

Seiko is not a watch brand that you would categorise as a luxury watchmaker. However, for those in the know, this is one that can rival even the most illustrious of houses in the art of watchmaking. We learn more about what sets Seiko apart from its contemporaries with the help of Hiraga Satoshi, the Master Craftsman.

“Compared with ‘regular’ movements, high-beat calibres are less sensitive to mechanical shocks and thus more accurate, but there are trade-offs that must be made. Firstly, because they require greater torque — which we accomplished in Grand Seiko’s 9S high-beat movement family with a taller mainspring — wear and tear is increased. Durability is thus an issue for some components, including the escape wheel. To make it more durable, we switched to manufacturing it using micro-electromechanical systems (MEMS) technology, which can fabricate parts with more complex outlines and to tighter tolerances. This production technique let us modify the escape wheel’s teeth from a sloped profile to a stepped one that has better lubricant retention, while also creating smoother teeth surfaces. The result is decreased friction between the escape wheel and pallet fork, and reduced wear and tear.

“The improvements in our high-beat movements’ durability have made it possible to prescribe longer service intervals for them. We used to recommend more frequent overhauls for our 36,000bph timepieces, but we now advise customers to send them in every three to four years instead, which is similar to watches with regular 28,800bph calibres.

Watchmaker Hiraga Satoshi

“Durability aside, the power reserve for high-beat calibres is also an issue, as their faster escapements deplete energy more quickly. In fact, one area that I’m working on now is finding out ways to improve the barrel and extend the power reserve by, for example, using new materials for the mainspring. We could extend the power reserve by using multiple barrels, of course, but using a single barrel allows us to keep the movement smaller.

“On a technical level, a high-beat movement isn’t any more difficult to produce than a normal movement. However, only a manufacture with the know-how can attain the movement durability and power management needed to create a functioning 36,000bph calibre. Only a few brands have put in the resources to clear these two hurdles, and that explains the relative scarcity of high-beat movements on the market today. Seiko is, of course, one of them.”

This article was originally published in WOW #43 (Festive 2016) issue.